Grab having the shells connected by enclosed lubricated slide bars



Dec. 2 1958 F. o. SNOW, JR

GRAB HAVING THE SHELLS CONNECTED BY ENCLOSED LUBRICATED SLIDE BARS 5 Sheets-Sheet 1 Filed Sept. 21, 1956 INVENTOR. 57605/7/6' 4. 5 0/14 BY v F. O. SNOW, JR GRAB HAVING THE SHELLS CONNECTED BY Dec. 2, 1958 ENCLOSED LUBRICATED SLIDE B R Flled Sept. 21, 1956 I A S 3 Sheets-Sheet 2 v Q NA Dec. 2, 1958 F. o. SNOW, JR

GRAB HAVING THE SHELLS CONNECTED BY ENCLOSED LUBRICATED SLIDE BARS 3 Sheets-Sheet 3 Filed Sept. 21, 1956 A INVENTOR. fieosfiwzr 0. Svam 02 United States Patent GRAB HAVING THE SHELLS CONNECTED BY ENCLOSED LUBRICATED SLIDE BARS Frederick 0. Snow, Jr., Maplewood, N. J., assignor to McKiernan-Terry Corporation, a corporation of New Jersey Application September 21, 1956, Serial No. 611,276

4 Claims. (Cl. 37-187) Particularly it is a purpose of the invention to avoid the objections present in prior constructions where with the shells connected by gearing or by open links, breakage and misalignment is frequently caused by the material being handled, such as ore, slag and the like getting into the exposed gearing and link mechanism.

Other special objects of the invention are to provide alignment and shell synchronizing mechanism which will be fully enclosed and protected, which may be kept properly lubricated, which in its operation will automatically reject and exclude material which might interfere with the action or cause breakage, and which will be free of projecting parts and not add bulk or increase overall dimensions of the machine.

The foregoing and other desirable objects are attained by the novel features of construction, combination and relation of parts as hereinafter described and claimed and illustrated by way of example in the accompanying drawings.

The drawings referred to show a present preferred embodiment of the invention, but it should be understood that structure may be modified and changed as regards the immediate illustration, all within the true intent and scope of the invention as hereinafter defined and claimed.

Fig. l in the drawings is a side elevation of a grab having the invention incorporated therein, showing the shells in closed position.

Fig. 2 is an end view of the grab.

Figs. 3 and 4 are enlarged broken part sectional views of one of the enclosed slide bars in the shell closed and shell open positions.

Figs. 5 and 6 are broken sectional views on substantially the planes 5-5 and 66 of Fig. 3.

Figs. 7 and 8 are details of the sliding link or bar and the stationary inner link, respectively.

The grab shown comprises a top or upper head 10 supported by holding rope 11, a lower or bottom head 12 supported by closing rope 13, links 14 pivoted at their upper ends to the top head at 15 and pivoted at their lower ends at 16 to the outercorners of the shells 17 which are pivoted at their innercorners to the lower head on hinge pins 18. The upper ends of the links are shown connected to rock together by a lateral projection 19 on one link operating in a companion socket 20 on the other link.

Alignment of parts is preserved and uniformity of shell movement is maintained by means of slide bars 21 in the form of elongated flat links pivotally connected with opposite shells by crank pins 22, 23 disposed above and below the centers of hinge pins 18 and having reversely faced arcuate slots 24, 25 to clear the hinge pins in the up and down and lateral travel of the links from 2,862,316 Patented Dec. 2, 1958 the bucket closed to the bucket open positions shown in Figs. 3 and 4.

Enclosures for such links are present in the form of inner stationary plates or links 26, Fig. 8, supported on the hinge pins at holes 27 and having reverse arcuate slots 28, 29 for passage of crank pins 22, 23 and an overlying outer stationary cover plate or link 30 pivotally supported on the hinge pins at 31, Fig. 6, these inner and outer plates joined over the top and down the sides by a cover flange 32.

, Thisstationary cover construction mounted on the crank pins provides a stationary parallel sided narrow slot confining and guiding the slide bar links. p

These guide slots for the sliding links at the opposite sides of the bucket are shown as left openat the bottom so as to drop out any foreign matter and so that the vertically and laterally operating slides will expel material from the slots in movement from the upper position,.Fig. 3, to the lower position, Fig. 4.

Lubrication of the enclosed slide bars is accomplished in the illustration by grease gun fittings 33 on the hinge plates 34 with passages 35 extending inward to the crank pins 22, 23 and the latter channeled as indicated at 36, Fig. 5, for passage of the grease or other lubricant to the moving parts.

Force feed lubrication can thus be effected to lubricate the crank pins and keep the crank pin bars in free sliding relation within their guiding and protective enclosures.

The hinge pins are utilized to form the supports for the enclosures of the slide bars and this simplifies assembly and use of fastenings, since the parts are held in their assembled relation simply by passage of the hinge pins 18 through the outer and inner cover plates 30, 26, and the arcuate slots 24, 25 in the intervening slide links.

By this assembly the slide bars are held properly connected with the shells simply by engagement over the crank pins 22, 23 which are fixedly secured in the shells 17 and hinge plates 34, Fig. 5.

The hinge pins 18 are shown in Fig. 5 as secured in sockets 38 in the bottom head by cross bolts 39 and as having enlarged flanged heads 40 for bracing and hold-' ing the enclosures or link housings in firmly supported relation.

Fig. 5 also shows how the hinge pins may be equipped with force feed lubrication fittings 41 for lubricating the shell bearings 37 and which may be arranged to carry some lubricant to the slide links as well.

With this construction, removal of one bolt in each hinge pin permits the hinge pin to be pulled out. This drops the outer cover plate 30, exposing the slide link 21 which then can be slid off over the crank pin after which the inner cover member 26 can be lifted off over the crank pin, the latter remaining attached to the shell and hinge plate.

The construction thus is particularly simple to take apart or assemble. The synchronizing connections are fully covered and lie close against the sides of the bucket. The operating mechanism is fully protected against rough materials being handled and can be kept well lubricated and in smooth, quiet operating condition.

The outer cover plates 30 may be continuous except for the openings for the hinge pins so as to fully cover and protect the slide links in all positions and they are shown as thick and heavy enough to form rigid spacers for the outer ends of the hinge pins.

What is claimed is:

1. Grab comprising companion shell sections, spaced hinge pins pivotally supporting the same, crank pins on said shell sections offset from the hinge pin centers, a link pivotally engaged on said crank pins, connecting said shell sections and a housing enclosing said link and crank connections, said housing being supported in stationary relation on said hinge pins and said link having clearance openings for said hinge pins in the movement of said link in opening and closing of the shell sections.

2. Grab comprising companion shell sections, spaced hinge pins'pivo tally supporting the same, crank pins On said shell sections oflset from the hinge pin centers, a link pivotally engaged on said crank pins, connecting said shell sections and a honsingenclosing said link-and crankconnections, said housing comprising inner and outer stationary cover plates mounted in stationary relation on said hinge pins at opposite sides of the link and said inner cover' plate having reversely faced arcuate slots for passage of said crank pins.

3. Grab comprising a bottom head, horizontally spaced hinge pins removably secured to said bottom head, companion shells hinged on said pins, a casing having spaced inner and outer cover plates removably supported on said hinge pins, a sliding link slidingly confined and engaged between said spaced cover plates, crank pins connecting said shells and link,- said crank pins being carried byrsaid shells laterally offset from said hinge pins and having pivotal engagement with said link, the inner cover plate 4 7 having slots for free passage of said crank pins and means on the shells for supplying lubricant to the crank p1ns.

4. Grab comprising companion shells, spaced hinge pins pivotally connecting said shells, crank pins mounted on said shells laterally oliset from the centers of said hinge pins, and a link pivotally engaged with said crank pins and operating clear of said hinge pins, a casing enclosing said linkand crank pins and removably supported .on said hinge pins, a bottom head having seats for said hinge pins and means for removably securing said hinge pins to said bottom head and releasable to permit removal of the hinge pins and separation of the link and easing from the shells.

References Cited in the file of this patent UNITED STATES PATENTS 992,799 Norris May 23, 1911 1,376,847 Williams May 3, 1921 2,486,544 Allard Nov. 1, 1949 2,668,377 Allard Feb. 9, 1954 

